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The interplay of math anxiety and math competence for later performance
(2022-07-04)
Math anxiety’s negative effects on performance are well-documented. The interplay of math anxiety and mathematical competence regarding later performance is underexplored. We investigated whether math anxiety’s detrimental effects on learning depend on previous mathematical competence. Hypothesizing a moderation effect, we expected that trait math anxiety should affect pupils of higher competence to a greater extent than pupils with lesser competence. Based on 8th graders in secondary school, we found the expected ...
Aufsatz
Leaching and Transformation of Perfluoroalkyl Acids and Polyfluoroalkyl Phosphate Diesters in Unsaturated Soil Column Studies
(2022-06-25)
Per- and polyfluoroalkyl substances (PFAS) are environmentally ubiquitous, anthropogenic substances with adverse effects on organisms, which shows the need to study their environmental fate and leaching behavior. In the present soil columns study, the leaching behavior and fate of nontransformable and transformable (precursors) were investigated. Ten nontransformable PFAS in two different soils, two precursors and two field soils, which were already contaminated with a mixture of PFAS, and two uncontaminated controls, ...
Aufsatz
Long-term sulfamethazine leaching simulation in two different soils using the MACRO model
(2022-02-16)
Physically based models have been part of many risk assessment studies concerning pesticide or nutrient transport within (sub)catchments or at plot scale, but they are only poorly validated for simulating the transport of veterinary medicinal products. Veterinary medicinal products not only pose a risk to the quality of our waters but also tend to accumulate in soils, where they are associated with the appearance of resistant bacteria and long-term leaching. In this study, the physically based leaching model MACRO ...
Aufsatz
Experimental analysis of liquid metal galinstan for electronics actuation
(2022-06-05)
The experimental interfacial tension measurements of galinstan as a function of applied DC voltages are presented. The measurements are based on a tailored, modified pendent drop setup to make it suitable for this experiment. The findings rationalise Galinstan corresponding to Marangoni flow that actuates under the influence of a change in interfacial tension, resulting from applied voltages. Galinstan is substantiated as an actuation medium to enable ON or OFF states by using a very low applied voltage (∼ 0.8V). The ...
Aufsatz
The velvet worm brain unveils homologies and evolutionary novelties across panarthropods
(2022-01-25)
Background:
The evolution of the brain and its major neuropils in Panarthropoda (comprising Arthropoda, Tardigrada and Onychophora) remains enigmatic. As one of the closest relatives of arthropods, onychophorans are regarded as indispensable for a broad understanding of the evolution of panarthropod organ systems, including the brain, whose anatomical and functional organisation is often used to gain insights into evolutionary relations. However, while numerous recent studies have clarified the organisation of many ...
Aufsatz
Study of Dynamics in Metallic MEMS Cantilevers - Pull-In Voltage and Actuation Speed
(2023-01-13)
For different metals and varying geometries, this paper presents simulations of electrostatically actuated MEMS cantilevers regarding their influence on pull-in voltage and actuation speed. Three-dimensional electromechanical modeling including many non-linearities has been performed to study some static but mainly dynamic features. The results show that the involved parameters have different influences on the actuation speed and pull-in voltage: lower length, higher thickness as well as lower density and higher ...
Aufsatz
Postdoctoral employment and future nonacademic career prospects
(2022-12-01)
Most recipients of doctorates leave universities some years after graduation, while little is known about their future non-academic career prospects. I report results from a novel microlevel database that links information about doctoral dissertations completed in Germany with doctorate recipients’ social security records. The results, based on graduates’ individual careers for five broader subject groups, indicate that postdoctoral periods do not result in a wage premium when changing to the non-academic sector.
Aufsatz
Can group identity explain the gender gap in the recruitment process?
(2022-12-27)
Despite evidence that the gender gap in the labour market favours men, aggregate findings from correspondence studies show that women are more likely than men to be invited for a job interview. We hypothesize that the predominance of women among recruiters may explain this somewhat puzzling finding; recruiters may favour applicants of their own gender. We use the data from a large-scale correspondence study to test this hypothesis. As expected, we find that female applicants are more likely to receive callbacks for ...
Aufsatz
Mechanisms of one-photon two-site double ionization after resonant inner-valence excitation in Ne clusters
(2023-01-30)
The role of interatomic and intermolecular energy and charge-transfer processes in weakly bound matter is currently lively debated due to emerging destructive low-energy electrons and radicals. Here, we discuss two mechanisms of single-photon two-site double ionization occurring competitively or subsequently to resonant interatomic Coulombic decay (rICD) in inner-valence (2s→np) excited Ne dimers and clusters. The first mechanism is photoelectron-impact ionization which is, in general, not related to resonant excitation, ...
Aufsatz
On the implementation of large period piece-wise linear Arnold cat map
(2022-04-26)
This paper presents a piece-wise linear cat map (PWLCM) obtained by perturbing the conventional quantized Arnold cat map (QACM) with a nonlinear term. The effect of the nonlinear term on the dynamics of the QACM is investigated. We show that the eigenvalues, hence the Lyapunov exponents of the PWLCM depend on the initial conditions, which is not the case for the QACM. As a result, the proposed PWLCM is a generalized form of the QACM, whose the period exponentially increases with respect to the precision, thus taking ...